The package, as it is built, excludes most of the extensions due to the way the
source determines whether to build them. The Makefile for iptables looks for
KERNEL_DIR (which the rpm sets to /usr) to find the kernel source which is then
used by dozens of test scripts (iptables-1.3.5/extensions/.*-test) to determine
if the kernel has features.
$ cat .CLUSTERIP-test
#! /bin/sh
[ -f $KERNEL_DIR/net/ipv4/netfilter/ipt_CLUSTERIP.c ] && echo CLUSTERIP
Without a valid KERNEL_DIR, these 40 or so tests fail and the extensions are not
available in the package. The really easy work around is to put a kernel into
/usr/src/linux and set KERNEL_DIR in the spec. But I suspect it would be
better to patch the tests.